Science-fiction writer Bruce Sterling once suggested that the increasing links between the post-Cold War US armed forces and Hollywood were creating something called the "military-entertainment complex". When you look at modern games you can see what he means.
Many combat flight simulators are old military hand-me-downs or have been put together by ex-armed forces programmers.
However, if you believe their PR departments, the real-world military are more concerned these days about "information war" attacks on the West's information infrastructure: virus raids on our precious data stores.
Now, rather than flying virtual helicopters, info-warrior wannabes can fool around with an altogether more modern combat simulator, courtesy of Israeli developer Kidum and its intriguing new game, Virus.
Bringing the info war right back home, Virus stages an attack on your own PC. It builds a 3-D game world out of whatever it finds on your hard drive - sound files, graphics, old documents, letters to the bank manager. As the virus worms its way through your system, you see your files being gradually "destroyed", with the resultant "body count" logged in a text window.
The idea came from Rona Segev, Kidum's CEO. Developing the game took around 18 months, explains Rani Bronstein, the head of programming. The toughest problem was implementing the basic idea - that the game world should be created from each user's own PC, which means effectively that no two users ever play the same game.
"In all other games there is already a known map or environment which has been created in advance. In Virus, while it loads, the game has to analyse your computer and take stuff from your hard disk in order to build the game world."
The other problem wasn't so much technical as conceptual. As Segev puts it: "What exactly should a file look like?" In other words, how do you make the intangible digital world look interesting?
Bronstein says that tackling this was a question of balance. "We tried to give the user the feeling that they had some connection to their machine but also to move on from the dull look of the computer. The enemies in Vi- rus were all like insects or bugs and the machines you control are more like something from Star Wars."
Extending this, the chief virus has a definite, not to say rather familiar personality and is a sort of Freddie Kruger of the artificial life world, complete with a line in dodgy black humour.
Overall, though Virus's core idea is novel enough, it plays like a cross between the sci-fi flight sim Descent and combat strategy games like Command And Conquer or Warcraft. So players have to go on various missions, build bases and supply lines in their PCs' various directories. Then when they encounter the enemy - usually techno-organic insectoid creatures - they get to indulge in some standard lock and load action.
And films like Tron (which dumped Jeff Bridges inside a computer) and Fantastic Voyage, in which Raquel Welch travelled round the human body in a miniaturised submarine, were also an influence, says Bronstein.
"We want to build on this feeling that someone is inside a system, a body or whatever, and has to build and to fight against a machine, which might be also be a kind of creature as well."
Planning for the next game is under way. Apparently, the results are being watched with interest by the Israeli government, which subsidised Virus's development. "This technology - the graphics engine, the mapping system in Virus - could be used in other fields apart from games. The government saw the potential and decided to help," says Bronstein. "This is common in Israel. The government is keen to help multimedia companies."